Path handlers must now return a response object similar to the
response objects of the PLT web server, encapsulating headers, mime
type, status code, and so on.
A response object in turn can contain an encoding of a body. The only
presently supported body type is a procedure which just prints the
body.
Other changes:
- split file-dir-handler.scm out from handlers.scm
- moved the ICON-NAME constructor parameters for file handlers to the
options
- removed input/output port redirections and work with paths
explicitly